Depends upon the year, and which 396 it is, but, 4, to 8 degrees advanced, or BTDC, should make it run best.
6 degrees advanced, or BTDC.
Right around 6 degrees advanced, with todays pump gas.
12 or 13 degrees
6 degreed advanced or BTDC.
I would set it by ear, and performance.
a Chevy 396 bear block ways, right at 200 pounds.
Yes.
about 685 pounds dry
yes
180, to 200.
No it is not an interference engine.
No, they did not. The smallest big block Chevy is the 396. They also made a small block and big block 400.